Radiation improves odds for some women after mastectomy

NEW YORK (Reuters Health) - Women who have their breasts
removed because of cancer may benefit from receiving radiation
if they still have traces of cancer in their lymph nodes,
suggests a new analysis.

Radiation reduced the risk of death and of cancer returning
among women who had cancer cells detected in the cluster of
nodes under the arms after a mastectomy. The nodes are part of
the lymphatic system, a conduit for immune and other cells.

"It has been clear for some time that women in whom the
disease has not spread to the lymph nodes in the armpits will
not benefit from radiotherapy," Sarah Darby told Reuters Health.

"It's been unclear what the benefit is for women with one,
two or three positive lymph nodes," she said.

Darby is one of the study's authors from the Early Breast
Cancer Trialists' Collaborative Group at the University of
Oxford in the UK.

The new findings are based on data from over 8,000 women who
were randomly assigned to either receive radiation or not after
having one or both breasts removed because of cancer. The data
were from 22 trials conducted between 1964 and 1986.

The researchers, who published their results in The Lancet,
had information about whether the women were diagnosed with
breast cancer again within about 10 years of receiving
radiation. They also knew whether the women had died by the
start of 2009.

They confirmed what had been known - that radiation did not
offer any benefits for women who had no lymph nodes test
positive for cancer after their mastectomy.

But for women who had one to three lymph nodes test positive
after their breasts were removed, they did find a noticeable
difference in cancer recurrence and death.

For example, women with positive lymph nodes had about a 46
percent risk of their breast cancer returning during the 10
years after their breasts were removed. That risk fell to about
34 percent over 10 years among women who received radiation.

Similarly, about 47 percent of the women who did not receive
radiation died of breast cancer by the start of 2009. That
compared to about 37 percent of women who received radiation.

Women who received radiation were also less likely to die
from any cause, compared to those who did not get radiation.

The benefits of radiation remained even among women who
received other treatments, such as chemotherapy.

"This actually will confirm a lot of what people started to
think about," Dr. Alphonse Taghian told Reuters Health.

He wasn't involved in the new study but is co-director of
the Breast Cancer Research Program and chief of breast radiation
oncology at Massachusetts General Hospital in Boston. He also
teaches at Harvard Medical School.

"My sense is that there is a majority of physician
oncologists who would use post-mastectomy radiation in patients
with one to three positive lymph nodes," Taghian said.

"There will still be cases that we'll agonize about and it's
not really clear cut, but there is no doubt that this study will
make an impact on how people think about the one to three
positive lymph nodes," he said.

Most professional guidelines do not recommend radiation for
women with one to three lymph nodes that test positive for
cancer, Darby said.

"I hope people will review the guidelines," she said. "I
would certainly expect the guidelines to change."

Due to the age of the data included in the study, however,
there are some caveats.

Specifically, the women included in this analysis had their
lymph nodes sampled or completely removed to see how many
contained cancer. Those procedures are not commonly used now.

Also, Taghian said, it's also important for people to know
that while radiation can cause heart problems or other cancers,
the technology has improved.

"We are more precise," he said. "We are able to protect
tremendously the tissue which doesn't need to be exposed to
radiation and we have a better understanding and knowledge of
the biology of the tumor. This should reduce the risk of having
major complications."

Dr. Philip Poortmans wrote in an accompanying editorial that
the results of the new analysis "clearly confirm" that
post-mastectomy radiation should be considered for patients with
one to three lymph nodes that test positive for cancer.

He is with the Department of Radiation Oncology at the
Institute Verbeeten in Tilburg, Netherlands.

Darby said it's important for women to talk with their
doctors about their treatment options.

"Breast cancer is a very complicated disease," she said. "In
each individual case it would be very hard for the patient to
know what's best. I would counsel women to talk about it with
their oncologists."

SOURCE: http://bit.ly/NOENqw and http://bit.ly/QbL4yr The
Lancet, online March 19, 2014.